Electrical power systems can be found in virtually all industrial areas, and they normally involve some form of circuitry for controllably transferring electrical power or energy to the intended load. A particular example of a commonly used power system is a power modulator, which can be regarded as a device that controls the flow of electrical power. When a power modulator is designed for generating electrical pulses it is also referred to as a pulse modulator or pulse generator. In its most common form, a power modulator delivers high power electrical pulses to a specialized load. By way of example, high power electrical pulses are utilized for powering microwave amplifier tubes in driving electron accelerator systems and/or microwave generating systems for applications such as medical radiation applications and radar applications.
A key component in power modulators is the pulse transformer, which basically comprises a transformer core, one or more primary windings and one or more secondary windings. The pulse transformer is used for transferring pulse energy from the primary side to the secondary side, normally with a change in voltage and current. The transformer core is made of some magnetic material, and the windings are generally made of copper wires. In operation, the transformer is often placed in a pulse transformer tank, where a suitable fluid such as oil can cool the components efficiently and provide electrical insulation.
Transformer cores for short pulses in the range of a few microseconds are usually made of wound tape of silicon iron. This tape is typically only 0.05 mm thick. This is necessary for the reduction of losses in the core. To allow for practical application of the coils/windings, the core is generally cut into two halves. When the halves are reconnected, the gap left must be minimized and therefore the surfaces have to be ground flat and possibly etched to eliminate shorts between the tape layers. There must also be a thin insulation between the halves for this reason.